1. Field of the Invention
This invention relates to medical apparatus for cleansing internal wounds; more particularly, it relates to a self-contained, disposable, portable, combined wound irrigator and evacuator.
2. Description of the Prior Art
The evacuation of fluids from a closed wound is a common medical practice. This is often done on completion of surgery. Fluid evacuation usually is accomplished through gravity drainage, pressure dressings or compression bandages or by negative pressure or suction, the latter being preferred. Conventional closed wound suction devices include power driven vacuum pumps, central suction systems, or evacuated bottles. While each of these evacuation systems effectively evacuates a wound, all except the evacuated bottles have many disadvantages because of their cost, noise and restriction on patient mobility resulting in the retardation of post-operative exercises, ambulation and rehabilitation. The evacuated bottle may provide mobility but has the disadvantages of cost and the necessity of having to have many available since when one bottle fills, it must be replaced. The filled bottle must be emptied, sterilized and re-evacuated.
In addition to evacuating fluids from a closed wound, it is frequently necessary to expose the wound site to a flow of an irrigating solution to bathe the infected area. This has been particularly true in the case of chronic osteomyelitis. In the past, wound bathing has generally been accomplished by means of gravitational flow, such as through an intraveneous device. Irrigation in this manner further restricts patient mobility.
The frequent necessity of bathing and evacuating a wound site has accentuated the need for a device which will eliminate the cumbersome, complicated, expensive and restrictive combination of irrigation equipment and evacuation equipment.
The disadvantages of the previous wound evacuation systems have, in part, been overcome by recent inventions such as those shown in U.S. Pat. Nos. 3,774,611 and 3,779,243. In both of these devices the evacuator comprises an evacuation chamber formed with resilient side walls which, after manual compression and release, tend to return to their original position. During return to their original position, they provide a reduced pressure on the interior of the container which, when connected to an internal wound by means of a catheter tube, effects evacuation of the wound. While these inventions overcome the serious disadvantages of power-driven vacuum pumps and central suction systems, they have their own disadvantages. Their major disadvantage is the possibility of accidental compression of the container at a time when it is undesirable.
Another disadvantage includes the necessity of inverting the container and compressing it to empty for re-use since this may disturb the patient. Furthermore, these devices are deficient in that they serve only one purpose, namely the removal of fluids from the wound. Thus, although these evacuation devices permit a certain amount of patient mobility, if wound irrigation is also necessary, the patient must be connected to a means for irrigating the wound, such as an intraveneous device. The necessity of combining the two systems, one for evacuation and one for irrigation, makes the entire system inconvenient, relatively expensive and cumbersome. While ostensibly a patient could be ambulatory by carrying an intraveneous bottle of irrigating fluid above his head and carrying or wearing an evacuator device, it is unlikely that such a situation would be considered a convenient solution.
Still another disadvantage of prior art evacuation devices is their wide variation of negative pressure over the specified filling range of the devices. When empty and fully compressed, these devices often provide a vacuum higher than necessary which might cause lesions if tissue is sucked into or against the drainage tube. On the other hand, as the container becomes filled with fluid, the vaccum is reduced often to a level where the vacuum is relatively ineffective and clots or other debris may clog the drainage tube. Wound evacuators presently commercially available have total pressure variations of about 130% or more.
This invention's co-pending Application Serial No. 618,482 filed Oct. 1, 1975, now U.S. Pat. No. 4,058,123, is an example of a device combining irrigation and evacuation that overcomes the disadvantages of the prior art. While this co-pending application serves the same advantageous function, the instant invention is significantly structurally different.
It is the disadvantages of the prior art with respect to mobility, expense, convenience, disposability, safety and utility that the present invention is intended to overcome.